Timing arrangement



Oct. 10, 1944'. J. w. BROWN 2,359,967

TIMING ARRANGEMENT Filed Dec. 29, 1941 ZSheets-Sheet 1 JAMES w. BROWNATTORNEY Oct. 10, 1944. .L-w. BROWN 2,359,967

TIMING ARRANGEMENT Filed Dec. 29, .1941 2 Sheets-Sheet 2 F|G.3 FIG 6 2n200131206 207 20a \T 209 g F |G. 4 F|G.5

, INVENTOR.

JAMES w. BROWN ATTORNEY Patented Oct. 10, 1944 UNITED TIMING ARRANGEMENTJames W. Brown, Anderson, Ind., assignor to Antomatic Electric,Laboratories, l nc., a corporation of Delaware Application December 29,1941, Serial No. 424,758

4 Claims. (or. 177-380) My invention relates in general to a. timingarrangement and more specifically to a device which operatesintermittently, under control of a counter, to transmit a predeterminednumber of impulses at a predetermined rate.

The main object of the invention is to provide an intermittentlyoperating control device, which operates independently of temperaturevariation to periodically control a, work circuit as many times asdesired at variable periods of time.

The control device as illustrated comprises a vacuum tube having a powersource and a relay in circuit therewith which operates periodically aslong as power is applied to the tube, to transmit impulses, of eithermake or break variety, over a worlr circuit. Adjustable means isprovided to control the speed of operation of the relay, and a counteris provided which may be set to the number of impulses which it isdesired to transmit and which is thereafter controlled by the relay tocount ofi the impulses and stop transmission after the proper number ofimpulses have been transmitted. In addition a key or starting device isprovided and a lock relay is 'shown as controlled by the key to maintainthe device in operation independent of the key and under control of thecounting device.

, Further features and objects will be apparent from the accompanyingdrawings and the following specification and claims.

In the drawings Figure 1 is a circuit diagram of one embodiment of myinvention. 1

Figure 2 is a circuit diagram of a modification of my invention.

Figure 3 is a front view of the counter, shown diagrammatically inFigures 1 and 2, with the front dial and pointer removed.

Figure 4 is a back view of the mechanism shown in Figure l.

Figure 5 is aside view of the mechanism taken from the right side ofFigure 4.

Figure 6 is a view of the indicator dial and. pointer as taken from theright of Figure 5.

This application is a continuation in part of my prior applicationSerial #376,843 filed January 31, 1941 which has become abandoned.

In Figure 1 of the drawings, Ill indicates a battery or source of powerof approximately 24- volts, one terminal ll being suitably grounded asat l2. The other terminal 13 is connected to a switch It and the switchI4 is connected by line I5 to a switch It, in turn connected to a lineH. The line I! from the terminal marked l includes two branches I8 and19. Branch l9 terminates switch member 2|, which in turn includes aprojecting portion 22 adapted to be cyclicly engaged.

When member 22 is engaged by pointer C and moved to the right thecircuit across the switch Ill-2| is opened. A line 23 from contact 2!leads to one terminal 24 of a double pole single throw switch. Anotherline 25 from line 23 leads to a 24-volt synchronous vibrator 26 ofstandard manufacture and from the same leads line 21 which is groundedas at 2B or connected to a terminal 29 and designated by the number 5.This unit 26 not only includes a vibrator but includes a transformerarrangement as well, and the two output terminals therefrom areconnected respectively to ground as at 30 and to the line 3| which isthe main supply line to the plate 32 of the tube '1 which is of vacuumtube.

Across the terminals of the output end of this synchronous vibratorcurrent supply arrangement, is a. condenser 33 which also is grounded asat 30 and this condenser smooths out the current supply in the outputcircuit of the vibrator in the well known manner. No further descriptionof the unit 26 is believed necessary since it is a standard structure.The voltage at the output end is approximately ISO-volts but may be anydesired voltage, depending upon the characteristics of the tube utilizedand the characteristics of the control circuit for the same, thesamehereinafter to be described more fully.

The other pole 34 of the double pole, single throw switch, reviouslydescribed, is connected by a line 35 to a switch member 36. This switchmember is adapted to engage a contact 31 connectedto the line l8,previously described, in opposition to a constraint normally holding36-41 open, whenever the magnet 38, grounded as at 39, and connected byline 40 to terminal 4| of the switch, is energihed. The terminal 42 ofthis switch is connected by line 43 to the junction 44 in a line 45including a terminal 46 carrying the number 4, in turn connected by line41 to the line l5 as at 48. Whenever the double pole switch is closedand switches l4 and it are closed and the switch 20 and 2| is closed,which is its normal position, current is supplied to the coil 38 to holddown or close the switch 36-31 and current is also supplied throughswitch l4 to the line 50, which leads to one terminal of the tubeheating filament 5l.-

This tube heating filament 5| is connected by line 52 to ground 53 andthis circuit is always maintained in closed circuit position and it willbe noted as hereinafter pointed out, that as long as the switch I4 isclosed; the filament of the tube will be heated. It takes about fiveseconds at normal temperature for this heating filament to become fullyheated for proper tube operation. The remainder of the control,previously specified, is utilized for other control purposes in relationto tube operation. The filament-5l in turn heats the cathode 54 of saidtube and maintains that cathode at the proper temperature at allelectrons at a predetermined rate, depending upon this particular propertemperature and other factorsrelative to which reference. will be hadhereinafter.

The tube includes the grid 55 which is the varying factor of the tubefor it will be obvious times, so that thecathode seeks or tends to emitJ 203 -by means of the holes shown. The"knurled knob 218 is rigid withthe outer end of sleeve 2|5 and therefore with pointer C and arm 2 l4.Thus pointer C'" may be moved to any position by knob 2l0 such as toposition 4 (Figure 6), by merely overcoming the tension of spring 2 l land causing the detent 2l5 to ride over the teeth of gear 205. Aftermanual setting of pointer C to any position the continued operation oi}-mag net 90,. wil step gear 205 throughv ratchet 201 and gear 206,carrying pointer step by step toward the zero point on dial C. Thepointer C is so adjusted that the last step to move it to zero positioncauses it to engage abushing 22 on the end of a spring 2! and move it,against its tension, out of engagement,with the spring 20 to stopfurther operations of the device until pointer C is moved away from itszero position. Thus if pointer C is to control the tubef'tovcausesubsequent deener- .4

gization of themagn'et, to transmit pulses over the exterior controlcircuit and also to transmit pulses to the operating magnet 90 of thecounter. The current supplied to the plate 32 is interrupted by theopening ofJthe switch 20-2l and hence, the duration of tube operation isdeterminable by the lengthof time that the switch 202l remains closed.

The counter which is operated to open the springs 20-2l after apredetermined number of impulses have been transmitted by magnet 60 toload A or B is shown in detail in Figures 3, 4, 5, and 6. In Figures 1and 2 only the indicator dial C, the pointer C, the operating orstepping magnet 00 and the control springs 20+2 ljare shown. Referringnow to Figures 3, 4, and 5, it will be seen that the counting mechanismcomprises a supporting plate 200 supporting an lmpuls'ing magnet 50'(Figure 4) by means. of bracket 2M and a stepping magnet 90 by means ofbracket 202 (Figures 4 and 5). plate 200 is a bracket 204 (Figure 3)fastened to plate 200 as indicated and having its free end acting as abearing for one end of a shaft 204, the other end of which has a bearingin plate h. Loosely mounted on shaft 204 is a large gear wheel 205 whichmeshes with the small gear 206. The gear 206 and a ratchet wheel 201 arerigid with each other and rotatable as a unit on a small shaft 208 whichhas a bearing at one end in plate 200 and one at the other end in abracket 209 fastened to plate 200 as shown. A holding pawl 2I0'(Figure3) is pivoted at point 2 in plate 200 and has a spring 2 I 2 normallyholding it in engagement with the .teeth of ratchet 201. The armature ,2l2 of magnet 90 is-bent at its outer end and extends through an opening2 l3. in plate 200 and carries at its end a pawl 2l3a which, when themagnet 901s energized engages a tooth" I of ratchet 201 to step the samewith gear 200 and through gears 206 and 205 to move pointers C -one stepcounterclockwise as seen in Figures 3 tor plate 0 when in position isfastenedto bracket On the opposite side 'of clockwise. Referring now toFigure 6 the indica- Q manually set to position 4'as shown in Figure 6itwill take. four energizations of magnet 90 to move the pointer to zeroposition and open provided and project through the back of bracket 203into the path'o'f arm C. The pin 22,2 limits the counterclockwisemovement of "pointer" C and the pin 223 limitsclockwise movement thereofwhen manually'set in aclockwise direction. "Pin rm 2I 4 which isslightly 223 is not engaged by a offset from arm C". I

The magnet 60 l'sthe usual type ofrelay having an'arm'ature 2l9 which ispivoted atone end on" heel piece 220 and carries a link 22l .on itsother end which flexes'springs l5 and out of engage ment with backcontacts" and 03 respectively iwhen magnet 60 is energized andinto-engagement with their front. contacts I0 and 84. 7

The purpose of .the doublepole, single throw switch and the magnet 30it'will be obvious, is to maintaincircuit' operationafter the switch 16has been momentarily closed manually'to initiate I 1 clrcuitcontrol'functioning and to maintain cir cuit conditioning for subsequent andcontinued circuit control. In other words, the magnet "38- and theswitch member 36 and 31 are so connected with'the switch l6 and arecontrolled thereby so i that current is supplied by it to the magnet 38and to the input circuit of vibrator'26, and fol lowing release of theswitch 15, this switch ly current arrangement -36-,3| continues to suppto the vibrator input circuit. 7 v

The remainder of this description relates to the arrangement whereby theperiodicity may be varied and whereby the frequency of operation for anygiven periodicity selected is obtained and these impulses at the givenrate for j which the system is adjusted may be utilized in 'a largenumber of commercialapplications.

For example, for bomb control purposes where an aeroplane is providedwith a large number 'of bombs arranged for sequential andjpe'ri'odic Idischarge, this invention is highly advantageous because it has beentested and over a twentyfour hour period of operation, there has "beensubstantially no I detectable variation1.ordepar-. 3 ture from thepredetermined intervaljbetween successive impulses. Secondly "thisparticular control arrangement at'n'ormal room tempera ture requires butfive seconds toiheat the vacuum.

tube filament and thus heat the cathode. Also, when the temperature is'reduced 'to '60? below zero Fahrenheitthe' time element for heatingtube operation was but whereby if there be any variation incident totemperature variation, the summation of such variations appears to besubstantially zero so that the correction factor due to temperaturevariation in useeither over a long period of time or incident todifferent altitudes is still zero, which makes this device peculiarlydesirable, applicable and satisfactory for multiple bomb dischargecontrol.

In further explanation, the pilot of the plane can whenever near thetarget or military objective, close the switch l4 and this switch I4, asstated, energizes the filament and that same operation of closing switchl4 either directly, electrically or otherwise, may open the doors of thebomb compartment, or the switch M can be automatically closed when thecontrol for opening the door of the bomb compartment is energized orwhen the doors are actually opened.

The aviator, after five to ten seconds have elapsed, depending upon thetemperature as previously set forth. so that the pilot is convinced thatthe tube is properly heated and the bomb sight registers on the target,can close the switch l6 which secures instantaneous operation of thecontrol for bomb release and as previously described, this circuitremains closed through the switch 36'3l as long as switch 20--2l remainsclosed. ,As each bomb is discharged in succession at a predeterminedrate, as hereinafter pointed out, the counting device is automaticallyactuated and registers the number of bomb discharges still to be made.If the pilot has set this counting device to actuate switch 20 2l afterten bombs have been discharged by turning knob 2E8 to move pointer C toposition l then when the ten bombs have been discharged, the maincircuit 'is opened and no further bombs are. discharged, and theindicator C stands at zero position.

If the pilot proceeds to a second target and is carrying additionalbombs and the same rate of discharge is to be maintained and the samenumber of bombs is to be dropped on the second military objective, thenthe pilot again closes switch It after the counting device has beenreset to position It) and when the bomb sight registers on the newtarget, the switch 16 isv closed and the same number of bombs is droppedin succession at the same rate.

The counting device is so. arranged that it will register any number ofoperations or bomb discharges. Following each seriesof operations, it isrequired to be moved from zero position which permits switch 20-2I toclose, and, the actuating member of this counter is then adjusted forthe desired number of bomb discharges, which may be the same as thefirst discharge series or a difierent number.

Inv explanation of the reason it is critical that a predetermined rateof operation'be obtained, the following by way of example only is given.If the military objective is a supply or troop train and if dependingupon the normal speed of the plane a certain time interval is requiredto register hits on the first, third, fifth, et cetera, or first,fourth, or seventh, et cetera, cars in the train, the periodicity ofoperation is adjusted in accordance with the normal speed of the planeto secure energization ofbomb release antomatically and repetitiously atthe predetermined rate to insure hits on the selected targets, asdefined above providing the aiming is right.

In bombing a column of troops or a military convoy of trucks or tanks,the same general plan is followed. Dumping all bombs in one position isnot military effectiveness. Demoralibombs be discharged at differentintervals; consequently provision is made herein and to which referencenow will be had, whereby the duration or interval may be adjusted andnot only will that be described but the normal functioning of thecircuit, whether it includes such adjustability or not will be setforth.

In the central portion of Figure 1 there is illustrated a magnet 60 andthis magnet is connected by a line 61 to the line 62, in turn connectedto one terminal of the cathode. The other terminal of this magnet 60 isconnected by a line 63 to the line 52 connected to the ground 53. Acondenser 64 is connected across the magnet 60. Magnet 60 imposes itseffect upon the switch members 15 and 80 of a material that hassubstantially a zero coefficient as far as temperature is concerned andwhich has a relatively long life insofar as crystallization is concerneddue to repetitious operation.

The line 62 has a branch connected to a contact spring 68'. A line 69 isconnected to the line 63 at one end and to a contact spring 10 at theother end, and these two contact springs 68 and 80 are spaced apart andare selectively engaged by theswitch member 15. The switch member I5 isconnected by a line 12 to an adjustable resistance 13 in turn connectedby line H to the control grid of the tube. Between the lines 62 and Mthere is connected a condenser I502. The adjustable resistance 13determines the rate of operation when the proper con denser 15a isutilized.

It will be remembered that the heating filament 5| has been energized;therefore, the cathode 54 has been properly heated. It also will beremember the plate 32 has proper potential imposed thereon. The normalidle position of the parts is with the switch member 15 elevated so thatit engages contact 68. When switch I6 is closed potential immediately issupplied to plate 32 which immediatelyv supplies energy to the coilfiflfover the plate circuit and when that is energized its armatureswitch member 15 is attracted and is pulled downwardly againstits normaltension and engages contact 10 and opens the normal circuit to thecontrol gridand connects the control grid circuit through resistance 73to the lower end of the coil 6.0, thereby changing the characteristicsof this circuit. Each energization of magnet also causes spring todisengage spring 83 and engage spring 84.

The effect of this transfer is that the characteristics of the vacuumtube change in the corresponding manner so that there is more negativepotential on the control grid than heretofore as soon as condenser 15abecomes charged and consequently, less current flows in the platecircuit and, therefore, there is less current in the magnet 60. Thissmaller current is insufficient to oppose the tension of springs 15 andTherefore, on this lower current condition becoming efiective, magnet 60deenergizes and opens the circuit across the contact 10 and II, thusreestablishing the circuit in its original position. The condenser 15a.is now discharged in the terminal bearing numeral 3.

' of 1,000 ohms.

4 I through adjustable resistor II and 'grid' II is restored to itsoriginal potential. It is the time.

' element determinable by the resistor 13 and condenser 150 thatdetermines the time element of operation of the magnet 60 and thus theperiodicity of the circuit for. control purposes can be accuratelyadjusted and maintained.

Each time magnet operates to move spring 80 into engagement with spring84 it closes a.

circuit for the stepping magnet 80 of the counter. This circuit extendsfrom battery through switch ll, conductor 41, conductor 45, springs 80and 84, and through magnet 80 to ground.

ationof magnet 90 and a consequent step of indicator pointer 0 one steptoward zero.

So far the circuit has been'seli-contained, as

I it were, and there has been no portion set forth which is effectivefor subsequent control. This is conventionally illustrated as follows:The switch member 80 which is simultaneously operated by magnet 60 mayhave upper and lower contacts 83 and 84 as shown each connected tolines. 85 and 86. Line 85 terminates in the terminal bearing numeral2--and line 88 terminates If it is desired to operate a device such asthe bomb release mechanism by closing a circuit, it will be obvious thatthe terminals of that control device, such as load B (shown dotted) must'be connected between terminal 3 and ground. If

the control is to be utilized for opening a circuit or 'controlpurposes, the terminals of that device such as load A (shown dotted) areconnected between the*terminal which is numbered 2 and ground. Thus'assuming device B to be connected for operation, then each time magnet60 is energized an impulse is sent over lead 68 from battery, leads Iand 45 and through springs 80 and 84 to lead 86 and to the device B torelease orie bomb and at the same time indicator C is moved one step torecord the release.

Each operation of magnet 60 therefore causes one oper In Figure 2 thereis illustrated a slightly diiferent form of the invention and herein thediflerence is in the tube T and in the addition of a condenser'lslbetween the lines I and I86. The other elements of the construction aredesignated by numerals similar to the primary form of the inventionnumeral designation but increased by 100.

' Both forms of the invention, if desired, may be provided with a pilotlight and in' Figure 1a line leading from the line' 35 connects to oneterminal of a 24-volt lamp 9!, the other termina of which is grounded asat 84. a Referring to the form of the invention illustrated in Figure 2,the filter I83 across the output of the vibrator is .5 microfaradcondenser. The

- adjustable resistance- I18 is between 250,000 and I 200,000 ohmscapacity. The condenser Ilsa is of two microfarad capacity. Thecondenser I acrossthe coil IE0 is microfarad in capacity. The coil I isapproximately 1250 ohms resist ance. The coil I38 has an approximateresistance The condenser IBI is approximately 100 microfarad capacityand this is variable, depending upon the external load con- I nectedacross the terminals I81 and I28. A condenser of similar character maybe interposed across line Sand I88 as indicated at I88.

The tube T is a 25A6 commercial vacuum tube and no further descriptionthereof is believed necessary. The absolute or approximate values of theresistances and condensers hereinbefore given, are based upon an assumedapplied voltaasaoev age .of 150- volts applied to the tube plate. Anyvariation or change in this. voltage of necessity will necessitate achange in the values of the elements previously set forth. The departurein the tube T'over the tube T is that the plate and cathode herein eachhas in multiple therewith an internal grid, not numbered butillustrated. Any triode vacuum tube or any pentode or multiple grid tubecapable of substantially functioning as a triode vacuum tube may beutilized in this circuit for the described control function.

While the invention has been illustrated and described in great detailin the drawings and foregoing description, the same is to be consideredas illustrative and not restrictive in I character.

The several modifications described herein as well as others which willreadily suggest themselves to persons. skilled in, this art, all areconsidered to be within the broad scope of the invention, referencebeing had to the appended claims.

The invention claimed is:

1. A system for controlling the number of impulses and the timing of theimpulses transmitted over the bomb release circuit of an aircraft,including'an electron discharge tube, a source of potential connectedthereto, a relay having its winding connected to the cathode of thetube, contacts on the relay connected to the grid ofthe tube, othercontacts on the relay connected to thebomb release circuit, said relayenergized over a circuit including said cathode and said source, tooperate said first contacts to thereby controlthe grid potential of saidtube to in turn cause intermittent operation of the relay and to operatesaid other contacts to send an impulse over said bomb release circuit,means for starting the operation of the relay, and means for continuingthe intermittent operation thereof independent of the starting meansuntil any predetermined number of impulses have been and tube of thetransmitter to interact to send impulses at regularly spaced intervalsto the bomb release mechanism and to the counter, an adjustable meansfor setting the transmitter 'to deliver impulses at intervals spaced inaccordance with the speedof the aircraft, a. relay controlled by thestart key for continuing the operation of the transmitter independent ofthe start key and under sole control of the counter, and meanscontrolled by the counter after it has been moved a number of steps inaccordance with its setting,

by the impulses received from said transmitter,

for preventing further transmission of impulses.

3. A system for controlling the release of trains of bombs from anaircraft, comprising a bomb release circuit, an electron discharge tubeand a relay, said relay connected tov the control electrode of saidtube, a condenser connected betweenthe cathode and the control electrodeof said tube, contacts on said relay in the bomb release circuit andother contacts controlling the charging and discharging of saidcondenser to in turn control the bias potential of said controlelectrode, means for starting the operation of said relay, the contactsof said relay when operated by said relay causing said condenser to bealternately charged and discharged to cause incondenser interacting totime the operation of said relay, said relay connected to the cathode ofsaid tube and energized in series therewith, said condenser connected toone cathode and grid of said tube, means for adjusting the dischargetime of said condenser, the charging and discharging of said condenserdetermining the speed of operation of said relay, contacts on said relayoperated by each energization thereof to transmit impulses to releasebombs, other contacts on the relay operated to control the release ofsaid controller from its preceding position, and other contacts thereoncontrolling the charging and discharging of said condenser. 7

JAMES W. BROWN.

